The importance of proper tube biasing

So I decided to check the bias on my FUCHS modded DRRI. It's had the same JJ 6V6's in there for awhile, and somehow, started to sound less than optimum. On checking the bias, turns out both tubes were at 17.3 mA with 435 on the plates. That's pretty cold,and I realized I had previously used the 12 watt 6V6 tube calculations to check on the bias levels instead of the 14 watt 6V6GT. So I increased the mA to the tubes to 22.5 mA. It does sound much better.